Air-compressor.



No. 764,182. PATENTED JULY 5, 1904. G. J. DIEDRICH & A. F. GRAMER.

AIR COMPRESSOR.

APPLICATION mum BEN. 24, 1902.

2 BHBBTB-SHEET 1.

NO MODEL.

7 @a/mer;

lg 11, viii-1 No. 764,182. PATENTED JULY 5, 1904.

CRAMER.

AIR COMPRESSOR.

APPLIGATION FILED SEPT. 24. 1903.

G. J. DIEDRIOH & A. F.

2 SHEETS-SHEET 2.

N0 MODEL.

Ira/672150 715, {QWZCJJJMTM g, finflwrg/fa am UNITED STATEs Patented July 5, 1904.

PATENT OFFICE.

CHARLES J. DIEDRICH AND ANTHONY F. CRAMER, OF DETROIT, MICHIGAN.

AIR-COMPRESSOR.

SPECIFICATION forming part of Letters Patent No. 764,182, dated July 5, 1904.

Application filed September 24, 1903.

Be it known that we, CHARLES J. DIEDRIOH and ANTHONY F. CRAMER, citizens of the United States, residing at Detroit, in the county of Vayne and State of Michigan, have invented a new and useful Improvement in Compressors, of which the following is a specification.

Our invention relates to an improvement in the class of fluid-compressors which we have particularly designed for the compressor of an ammonia ice or refrigerating machine, though it is intended for'use also with any compressor in the class referred to.

In compressors of ammonia ice-machines now in common use the object is attained of the minimum of lost motion or clearance of the piston by setting the valve close to the ends of the piston-stroke, but with the disadvantage of parts of the valve mechanism in case of fracture falling into the cylinder,with consequent dangerous and disastrous results. The attempt has been made to overcome this difficulty by setting the valves in chambers outside the cylinder proper, thereby sacrific ing the advantage due to avoiding clearance; and the primary object of our improvement is in overcoming the diificulty with the same sacrifice to afford a material reduction in the amount of lost motion of the piston. This object we accomplish by the construction illustrated in the accompanying drawings, in which- Figure 1 is a vertical longitudinal section of an ammonia ice-machine compressor provided with our improvement. Fig. 2 is a view of the same in end elevation; and Fig. 3 a section taken on the irregular line 3, Fig. 1, viewed in the direction of the arrow and enlarged.

A is the cylinder, containing the piston B and provided transversely with the chambers C and D, preferably on its opposite ends and below the longitudinal center thereof, as

shown, communicating with the cylinder respectively through the upwardly-inclined C6D".

tral ports 0 and D. At opposite sides of the transverse center of each chamber C and D are formed the converging valve-seats a and a, respectively, for the inwardly opening Serial No. 174,437. (No model.)

spring-pressed suction-valve E and the outwardly-opening spring-pressed delivery-valve F. The valves on their spring-pressed stems are preferably of the construction illustrated in Fig. 3; but, as shown, they involve no features of novelty and need not, therefore, be described herein in detail. The converging valve-seats in each chamber D and 0 form between them a tapering pocket t, with the port at the inner end of the pocket of the same cross-sectional area as that of either valveseat opening, for the-purpose hereinafter eX-' plained.

In the stroke of the piston toward the chamber D it sucks gas into the cylinder past the valve E in the chamber C and discharges the gas ahead of it by opening the delivery-valve F in the chamber D, and the opposite stroke of the piston sucks gas into the cylinder past the valve E in the chamber D and discharges it by opening the delivery-valve Fin the chamber C. Obviously, however, neither valve will be opened by the action of the piston until it has, on the one side, sucked out of the pocket?) the volume of gas contained therein sufficiently to permit the valve-spring to act, and, on the other side, introduced into the respective pocket 6 the volume of gas it is adapted to receive. Hence the clearance or lost motion, due to the provision of the pockets. This lost motion is in a measure compensated for by increasing either the diameter, as in the present case, or the length of the cylinder A; but it is undesirable to so increase it sufficiently to compensate entirely for such lost motion, thereby to attain the full efficiency of the compressor. Hence we provide the pocket 6, and to reduce under the existing conditions to the minimum the volume of the gas in the pocket, and therefore the quantity thereof to be compensated for, we reduce the area by tapering it, but providing each port C D of the full area of either valve-seat opening from which it leads.

In thus compensating for the lost motion of the piston we attain the advantage of assisting its action by the expansion against it of the clearance gas or that sucked out of the clearance formed by the pocket from which it is drawn.

While our improvement is shown in connection with a double-acting compressor, we intend it also for use witha compressor of the single-acting variety.

What we claim as new, and desire to secure by Letters Patent, is-

1. In a compressor, the combination with the cylinder, of a chamber exterior to and extending transversely across the base of the cylinder proper and containing converging valve-seats forming between them a tapering pocket leading to a port through which said chamber communicates with the cylinder, a spring-pressed suction-valve in said chamber at one of said seats, and a spring-pressed delivery-valve in said chamber at the other of said seats.

2. In a compressor, the combination with the cylinder, of a chamber exterior to and extending transversely across the base of the cylinder proper and containing converging valve-seats forming between them a tapering pocket and a port, to which said pocket leads, of the area of either valve-seat opening, and through which said chamber communicates with the cylinder, and spring-pressed suction and delivery valves seating inclinedly against said seats.

3. In a compressor, the combination with the cylinder of a chamber exterior to and extending transversely across the base of the cylinder proper, converging valve-seats at opposite sides of the transverse center of said chamber forming therein a tapering pocket and a port, to which said pocket leads and through which said chamber communicates with the cylinder, and spring-pressed suction and delivery valves in said chamber seating against said seats.

4 In a compressor, the combination with the cylinder of exterior chambers extending transversely across the base of the cylinder proper near its outer ends, a pair of converging valve-seats in each chamber forming between them a tapering pocket and a port, to which said pocketleads, and through which the chamber communicates with the cylinder, and spring-pressed suction and delivery valves in each chamber seating inclinedly against said seats.

CHARLES J. DIEDRICH. ANTHONY F. CRAMER.

In presence of- ANTHONY F. CRAMER, J r., CAsPAR MANNEBACH. 

